Bismillaah
Ibn Rajab al-Ḥanbalī’s book, “Jāmi’ al-‘Ulūm wal-Ḥikam,” is an explanation of the forty-two famous ḥadīth collected by Imām an-Nawawī. The part of the  ḥadīth explained in this article is ḥadīth number twenty-four of that book.
The Explanation of:

يَا عِبَادِي إِنَّكُمْ لَنْ تَبْلُغُوْا ضُرِّي فَتَضُرُّوْنِي، وَلَنْ تَبْلُغُوْا نَفْعِي فَتَنْفَعُوْنِي

“Oh my servants, you will never be able to harm me, and you will never be able to benefit me.”
People are incapable of ever reaching a state in which they could benefit or harm Allah, for Allah is the Self-Sufficient, the Praiseworthy. He neither needs the obedience of his servants, nor does any benefit of such obedience reach him. It is only the servants who benefit from their obedience. Likewise, he is not harmed in any way by their disobedience, but it is they who harm themselves therewith. Allah ( تَعَالَى ) says:

وَلا يَحْزُنكَ الَّذِينَ يُسَارِعُونَ فِي الْكُفْرِ إِنَّهُمْ لَن يَضُرُّوا اللَّهَ شَيْئًا

And do not be grieved by those who hasten into disbelief. They will certainly never harm Allah at all.[Sūrah Āli ‘Imrān, 3:176]
And he says:

وَمَن يَنقَلِبْ عَلَى عَقِبَيْهِ فَلَن يَضُرَّ اللَّهَ شَيْئًا

And he who turns back on his heels will never harm Allah at all.[Sūrah Āli ‘Imrān, 3:144]
And Allah ( عَزَّ وَجَلَّ ) says:

وَإِن تَكْفُرُوا فَإِنَّ لِلَّهِ مَا فِي السَّمَاوَاتِ وَمَا فِي الأَرْضِ وَكَانَ اللَّهُ غَنِيًّا حَمِيدًا

But if you disbelieve, then to Allah belongs whatever is in the heavens and whatever is on earth. And ever is Allah free of need, praiseworthy. [Sūrah al-Nisā, 4:131]
And he says, quoting the prophet Moses:

وَقَالَ مُوسَى إِن تَكْفُرُوا أَنتُمْ وَمَن فِي الأَرْضِ جَمِيعًا فَإِنَّ اللَّهَ لَغَنِيٌّ حَمِيدٌ

And Moses said, “If you should disbelieve, you and whoever is on the earth entirely, indeed, Allah is Free of need, praiseworthy.” [Sūrah Ibrāhīm, 14:8]
And Allah says:

وَمَن كَفَرَ فَإِنَّ اللَّهَ غَنِيٌّ عَنِ الْعَالَمِينَ

And whoever disbelieves, certainly Allah free of need from all creations.[Sūrah Āli ‘Imrān, 3:97]
And:

لَن يَنَالَ اللَّهَ لُحُومُهَا وَلَا دِمَاؤُهَا وَلَٰكِن يَنَالُهُ التَّقْوَىٰ مِنكُمْ

Neither their meat, nor their blood (e.g., of animals slaughtered for charity) reaches Allah; but what reaches him is piety from you.[Sūrah al-Ḥajj, 22:37]
Allah ( تَعَالَى ) loves his servants to remain conscious of him and obey him, just as he dislikes them to disobey him. For this reason, Allah is happier with people’s repentance than the happiness felt by a person who, having lost his riding animal in a vast desert upon which are his food and drink, searches desperately for his mount to the point of exhaustion and finally, giving up all hope of ever finding it, gives in to certain despair that his life is as an end, and he abandons himself to death. As he succumbs to his exhaustion and sleeps, he later wakes up to find his riding animal standing right before him. This is one of the highest levels of happiness imaginable among creation.[51]
Allah is even happier than such a person despite the fact that he is in no way in need of his servants’ obedience or their repentance. Rather, he returns the benefit thereof back to them out his generosity and kindness toward his servants and his love for their well-being and his desire to prevent harm from reaching them. And in return, he loves for his servants to know him, love him, fear him, remain constantly aware of him, and to obey him and exert effort in getting closer to him. He loves for them to know that no one else can forgive their sins and that he is fully capable of showing forgiveness for the sins of his servants.
And in another narration of this ḥadīth from ‘Abdul Raḥmān Ibn Ghanam from Abū Dharr, it is reported that Allah said, “Whoever among you knows that I am capable of showing forgiveness and were he to ask for my forgiveness, I would forgive him and would not mind at all.”

The Explanation of:

يَا عِبَادِي لَو أَنَّ أَوَّلَكُمْ وآخِرَكُمْ وَإِنْسَكُمْ وَجِنَّكُمْ كَانُوْا عَلَى أَتْقَى قَلْبِ رَجُلٍ وَاحِدٍ مِنْكُمْ مَا زَادَ ذَلِكَ فِي مُلْكِي شَيْئًا، يَا عِبَادِي لَو أَنَّ أَوَّلَكُمْ وآخِرَكُمْ وَإِنْسَكُمْ وَجِنَّكُمْ كَانُوْا عَلَى أَفْجَرِ قَلْبِ رَجُلٍ وَاحِدٍ مِنْكُمْ مَا نَقَصَ ذَلِكَ مِنْ مُلْكِي شَيْئًا

“Oh my servants, if the first of you and the last of you, the people and jinn among you, were all to have hearts as righteous as the most righteous man among you, that would not increase my kingdom in anything. Oh my servants, if the first of you and the last of you, the people and jinn among you, were to have hearts as wicked as the most wicked man among you, that would not decrease my kingdom in anything.”
This shows that the kingdom of Allah will not increase in anything even if all creatures were as pious and had hearts as the most righteous person among them. Similarly, his kingdom will never decrease by the sins of sinners even if all the jinn and humans were to be as cruel and evil, having hearts as evil as the most wicked person among them. Allah ( سُبْحَانَهُ ) is self-sufficient, having no need whatsoever of anyone else. There is absolute perfection in his self, his characteristics, and in his actions. His dominion and authority is also perfect with no weakness or flaws to diminish it in any way.
Some people believe that the creations brought about by Allah – those present now – are the most perfect forms than had Allah created them in any other way. And the evil we witness among creation is a conditional type of evil dependent on some things within creation; it is not an absolute evil existing in creation such that its nonexistence would be better than its current existence under all circumstances. Rather, the fact that such aspects of evil are present is actually better than if they were not. They say that such an understanding is the meaning of Allah’s statement:

بِيَدِكَ الْخَيْرُ

In your hand is all good. [Sūrah Āli ‘Imrān, 3:26]
And this is the meaning of the prophet’s ( صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ ) statement:

الشَّرُّ لَيْسَ إِلَيْكَ

Evil is not to be attributed to you. [Muslim (no. 771)]
Meaning: Absolute evil – that which the absent thereof would be better than its presence – is not present in your dominion. This kind of absolute evil is not to be found in Allah’s kingdom because Allah ( تَعَالَى ) brings about his creation and what it requires of wisdom and justice. Sometimes he distinguishes particular people (perhaps in this life or the next) with favors which he does not give others out of his justice and what that necessitates of complete wisdom.
Yet in such an understanding there is an issue which contradicts the point being made in the ḥadīth in that were all creations to have the best characteristics of piety and righteousness, that would not increase and improve his dominion at all. And were all the creations to have wicked characteristics that would lower the status and manner in which they were initially created, that would still not decrease the dominion of Allah in any way. [In other words, perhaps it is possible to become better or worse than one’s initial creation due to belief or disbelief in Allah, obedience or disobedience, etc.] And this (the fact that people have the choice to become better or worse) shows that Allah’s dominion and kingdom are still perfect in every way; it can neither be improved, nor perfected or completed even by obedience just as it cannot be decreased by disobedience. Nothing at all affects its perfection.
These statement (of the ḥadīth) mentioning the heart also indicate that the source of righteousness and wickedness is the heart. When the heart is pious and conscious of Allah, the (actions of the) limbs will be righteous, and when the heart is evil, the limbs will be likewise.[54] Because of this, the prophet ( صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ) said:

التَّقْوَى هَا هُنَا

Righteousness is right here.
And he pointed to his chest.[Muslim (no. 2564)]

Footnotes:

[51] This comparison is taken from a ḥadīth in which the prophet ( صلّى الله عليه وسلّم ) said:

لَلَّهُ أَشَدُّ فَرَحًا بِتَوْبَةِ عَبْدِهِ حِينَ يَتُوبُ إِلَيْهِ مِنْ أَحَدِكُمْ كَانَ عَلَى رَاحِلَتِهِ بِأَرْضِ فَلاةٍ فَانْفَلَتَتْ مِنْهُ وَعَلَيْهَا طَعَامُهُ وَشَرَابُهُ، فَأَيِسَ مِنْهَا، فَأَتَى شَجَرَةً فَاضْطَجَعَ فِي ظِلِّهَا قَدْ أَيِسَ مِنْ رَاحِلَتِهِ فَبَيْنَا هُوَ كَذَلِكَ إِذَا هُوَ بِهَا قَائِمَةً عِنْدَهُ فَأَخَذَ بِخِطَامِهَا ثُمَّ قَالَ مِنْ شِدَّةِ الْفَرَحِ: اللَّهُمَّ أَنْتَ عَبْدِي وَأَنَا رَبُّكَ! أَخْطَأَ مِنْ شِدَّةِ الْفَرَحِ

Allah is happier with the repentance of his servant when he repents to him than if one of you were traveling on his riding animal in a vast desert but it escapes while carrying his food and drink. After giving up all hope of catching it, the man then reclines in the shade of a tree, having despaired of finding his mount. While in such a state, he suddenly finds it standing right next to him so he takes its reins and cries out from sheer joy, “Oh Allah, you are my servant and I am your lord!” He makes such a mistake only from extreme happiness.
[Recorded by Muslim (no. 4939) and al-Bukāhrī” (no. 5863).]
[54] This point has been reported in a ḥadīth in al-Bukāhrī (no. 52) and Muslim (no. 1599) in which the prophet ( صلّى الله
عليه وسلّم ) said:

أَلا وَإنَّ فِي الْجَسَدِ مُضْغَةً إذَا صَلَحَتْ صَلَحَ الْجَسَدُ كُلُّهُ ، وَإِذَا فَسَدَتْ فَسَدَ الْجَسَدُ كُلُّهُ ، ألا وَهِيَ القَلْبُ

There is within the body an organ, if it is pure the entire body will be purified, and if it is corrupt, the entire body will be corrupted. It is certainly the heart.
Posted from: The Forbiddance of Oppression - Ibn Rajab al-Hanbali, Translated by Abu az-Zubayr Harrison
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